Portable key seat cutter for shafts

Abstract

The key seat cutter consists of a portable frame adapted to be clamped on a shaft and having a cutter and a cutter drive mechanism mounted on a slide reciprocable on the frame by a manually rotatable lead screw. The input to the drive mechanism consists of a stub shaft adapted to be connected with the chuck of an electrical hand drill.

I claim: 
     
       1. A portable tool for cutting a longitudinally extending key seat in a work shaft comprising, a generally rectangularly shaped, main support frame having spaced front and rear upright end bars, a lower support bar extending between and connecting the lower ends of the end bars and an upper guide bar extending between and connecting the upper ends of the end bars, said guide bar forming a rectilinear guideway between said end bars, said front end bar having an opening therein above the support bar through which the free end portion of a work shaft is adapted to be extended, means for clamping said work shaft in said opening, an upright support block mounted on said support bar and adjustable lengthwise thereof, said support block being adapted to engage and support a portion of the work shaft extending through said opening and cooperating with said front end bar for rigidly mounting the frame in a fixed position on a work shaft such that the guideway extends lengthwise of and above the shaft on which the frame is clamped, a slide mounted for rectilinear movement on said guideway, a manually rotatable lead screw extending between said end bars and parallel to said guideway, said lead screw being connected with said slide to shift the slide lengthwise of the guideway when the screw is rotated, a carriage supported on said slide for movement therewith and pivotable thereon about a horizontal axis perpendicular to the path of travel of the slide toward and away from the shaft on which the frame is mounted, means for pivoting the carriage in a vertical plane about said axis on the slide, a drive train on said carriage having an input shaft, a horizontally extending output shaft and gears interconnecting said shafts, said input shaft comprising a stub shaft adapted to be connected with the chuck of a hand-held, power driven drill, said output shaft being journalled on said carriage adjacent the front end thereof and having a rotary key seat cutter mounted thereon for rotation in the axial plane of the work shaft on which the frame is mounted, said output shaft being spaced radially from and forwardly of the pivot axis of the carriage on the slide so that the key seat cutter is displaced in a vertical plane toward and away from the axis of the work shaft in response to pivotal movement of the carriage, said drive train being driven by said input shaft and being free of a driving connection with the lead screw so that rotation of the cutter is independent of its adjustment lengthwise of the shaft, whereby, when the input shaft is connected to the rotating chuck of a hand-held drill, the cutter can be fed radially into the work shaft to cut an arcuate slot therein and can then be advanced lengthwise of the frame by rotating said lead screw to cut a key slot lengthwise of the shaft to the free end thereof. 
     
     
       2. A tool as called for in claim 1 wherein the lower portion of the rear end bar has an opening therein aligned with the opening in the front end bar and through which the work shaft can extend so that the frame can also be mounted on a work shaft intermediate its ends. 
     
     
       3. A tool as called for in claim 2 wherein said carriage and the drive train to the output shaft is offset laterally to one side of said frame so that the cutter can be advanced to a position directly adjacent the front end bar without obstruction between the frame and carriage. 
     
     
       4. A tool as called for in claim 1 wherein the connection between the support bar and the rear end bar is adjustable vertically of the rear end bar so that the support bar can be inclined to the path of travel on the carriage to enable cutting a key seat on a tapered portion of a work shaft. 
     
     
       5. A tool as called for in claim 1 wherein said guide bar is of generally rectangular cross section and said slide comprises a block having a slot therein corresponding with the cross sectional shape of the guide bar and interfitting therewith.